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Optical true time delay pool based hybrid beamformer enabling centralized beamforming control in millimeter-wave C-RAN systems

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Science China(Information Sciences) 2021年第9期64卷 202-211页

作者： huan huanG Chongfu ZHANG Muchuan YANG Wei zheng Jie PENG Kun QIU School of Information and Communication Engineering Zhongshan InstituteUniversity of Electronic Science and Technology of China School of Electronic Information University of Electronic Science and Technology of ChinaZhongshan Institute

Effectively supporting millimeter-wave(mmWave) beamforming is still a major challenge in 5 G cloud radio access network(5 G C-RAN) systems with evolved common public radio interface-based(eCPRIbased)fronthaul. Herein, an optical true time delay pool based hybrid beamforming(OTTDP-HBF) scheme,enabling centralized beamforming control, is proposed for mmWave 5 G C-RAN systems. The weight control of the OTTDP-HBF is physically implemented by a pre-designed optical wavelength matrix which is mapped from a series of optical carriers. After introducing optical true time delay, this optical wavelength matrix then maps to the defined OTTDP. In this scheme, all physical implementation and the computational processing of analog beamforming can be centrally deployed into a centralized unit or distributed unit(CU/DU).Each active antenna unit(AAU) therefore becomes very simple. For single-user and multi-user scenarios,the OTTDP-based hybrid precoders are formulated respectively. In the developed OTTDP-based multiuser hybrid precoder, the spectral efficiency is improved by making use of all RF chains. For a 9-element uniform planar array deployed at an AAU, a designed example of the OTTDP-HBF is presented, where spectral efficiency curves obtained via different precoding schemes for single-user and multi-user scenarios are compared and discussed respectively.

关键词： optical true time delay MIMO system millimeter wave cloud radio access network multi-user hybrid precoding

PhIO-mediated Synthesis of Ketones from Aikynes and Alkenes

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Chemical Research in Chinese Universities 2019年第1期35卷 26-32页

作者： WEI ying zheng Xiangping XIE Xinmiao Center for Molecular Systems and Organic Devices(CMSOD) Key Laboratory for Organic Electronics and Information Displays &Jiangsu Key Laboratory for BiosensorsInstitute of Advaneed Materials(LAM) Jiangsu National Synergetie Innovation Center for Advaneed Materials(SICAM) Nanjing University of Posts & TelecommunicationsNanjing 210023P.R.China

A facile and efficient method for the preparation of methyl ketones was developed in the reaction of alkynes and alkenes with PhIO-BF3·*** reaction features mild conditions,short time and metal-free *** possible mech... 详细信息

关键词： Alkyne Alkene Ketone Hydration reaction

Fatigue Crack Propagation Analysis of Orthotropic Steel Bridge with Crack Tip Elastoplastic Consideration

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Computer Modeling in Engineering & Sciences 2021年第5期127卷 549-574页

作者： ying Wang zheng Yan Zhen Wang Jiangsu Key Laboratory of Engineering Mechanics Southeast UniversityNanjing211189China China Railway Major Bridge Reconnaissance and Design Institute Co. Ltd.Wuhan430056China

Due to the complex structure and dense weld of the orthotropic steel bridge deck(OSBD),fatigue cracks are prone to occur in the typical welding *** residual stress(WRS)will cause a plastic zone at the crack *** this paper,an elastoplastic constitutive model based on the Chaboche kinematic hardening model was introduced,and the extended finite element method(XFEM)was used to study the influence of material elastoplasticity and crack tip plastic zone on the law of fatigue crack *** judging the stress state of the residual stress field at the crack tip and selecting different crack propagation rate models to investigate the crack propagation law when plastic deformation was considered,the propagation path and propagation rate of fatigue crack of the OSBD were *** results show that,whether the residual stress field is considered or not,the plastic deformation at the crack tip will not cause the obvious closure of the fatigue crack at the U-rib toe during the crack propagation process,but will significantly affect the crack propagation *** material plasticity is considered,the propagation angle of fatigue crack at the U-rib toe basically remains unchanged along the short-axis direction of the initial crack,but is going up along the long-axis direction,and the crack tip plastic zone inhibits the propagation of the crack tip on one *** with linear elastic materials,the crack propagation law considering material plasticity is more consistent with that in actual bridge *** terms of the propagation rate,if the residual stress field is not considered,the fatigue crack propagation rate at U-rib toe with plasticity considered is slightly higher than that without plasticity considered,because plastic deformation will affect the amplitude of energy release *** considering the WRS field,the fatigue crack propagation rate at U-rib toe is increased due to the combined actions of plastic deformation and stress ratio R

关键词： Extended finite element fatigue crack propagation orthotropic steel bridge deck welding residual stress plastic deformation

miRNAs： novel regulators of autoimmunity-mediated pancreatic β-cell destruction in type 1 diabetes

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Cellular & Molecular Immunology 2017年第6期14卷 488-496页

作者： ying zheng Zhen Wang Zhiguang Zhou Center for Medical Research The Second Xiangya Hospital Central South University Changsha Hunan 410011 China Department of Metabolism and Endocrinology The Second Xiangya Hospital Central South University Changsha Hunan 410011 China Key Laboratory of Diabetes Immunology Ministry of Education National Clinical Research Center for Metabolic Diseases Central South University Changsha Hunan 410011 China

MicroRNAs （miRNAs） are a series of conserved, short, non-coding RNAs that modulate gene expression in a posttranscriptional manner, miRNAs are involved in almost every physiological and pathological process. Type 1 diabetes （TID） is an autoimmune disease that is the result of selective destruction of pancreatic p-cells driven by the immune system, miRNAs are also important participants in TID pathogenesis. Herein, we review the most recent data on the potential involvement of miRNAs in TID. Specifically, we focus on two aspects： the roles of miRNAs in maintaining immune homeostasis and regulating β-cell survival and/or functions in TID. We also discuss circulating miRNAs as potent biomarkers for the diagnosis and prediction of TID and investigate potential therapeutic approaches for this disease.

关键词： autoimmunity β-cell destruction miRNA type 1 diabetes

Iron oxidation-reduction bioavailability in and its impacts on cadmium paddy soils： a review

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Frontiers of Environmental Science & Engineering 2012年第4期6卷 509-517页

作者： Chunhua ZHANG ying GE huan YAO Xiao CHEN Minkun HU Demonstration Laboratory of Elements and Life Science Research College of Life ScienceNanjing Agricultural UniversityNanjing 210095China Department of Environmental Science and Engineering College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China

Redox conditions in paddy soils may vary as they are submerged and drained during rice growth. This change may bring about reductive dissolution of iron （Fe） oxides and subsequent formation of secondary Fe-bearing minerals in rice paddies. The mobility and bioavailability of metal contaminants such as cadmium （Cd） in paddy soils are closely related to the chemical behaviors of Fe. Therefore, in this paper, advances in the study of paddy Fe redox transformations and their effects on Cd availability to rice are briefly reviewed. Current concepts presented in this review include the forms of Fe in paddy soils, the reactions involved in Fe oxidation-reduction, chemical factors affecting Fe redox processes, Cd availability to rice and the impacts of Fe transformation on Cd uptake and translocation in rice. Prospects for future research in this area are also discussed.

关键词： paddy soil redox iron cadmium bioavail- ability rice

The Distance Coloring of Graphs

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Acta Mathematica Sinica,English Series 2014年第9期30卷 1579-1587页

作者： Lian ying MIAO Yi zheng FAN Institute of Mathematics China University of Mining and Technology School of Mathematical Sciences Anhui University

Let G be a connected graph with maximum degree △≥ 3. We investigate the upper bound for the chromatic number Xr（G） of the power graph Gr. It was proved that Xr（G） ≤ △ （△-1）r-1/△-2 ＋1 =M ＋ 1, where the equality holds if and only if G is a Moore graph. If G is not a Moore graph, and G satisfies one of the following conditions：（1） G is non-regular, （2） the girth g（G）≤2r - 1, （3） g（G） ≥ 2r＋ 2, and the connectivity k（G） ≥ 3 if r ≥ 3, k（G）≥4 but g（G）〉 6 if r= 2, （4） A is sufficiently larger than a given number only depending on % then Xr（G） ≤ M - 1. By means of the spectral radius λ1（G） of the adjacency matrix of G, it was shown that X2（G） ≤λ1（G）2＋ 1, where the equality holds if and only if G is a star or a Moore graph with diameter 2 and girth 5, and Xr（G）〈 λ1（G）r＋ 1 if ≥ 3.

关键词： Distance coloring power graph spectral radius

lncRNA-BBOX1-2通过调控成纤维细胞生长因子受体1促进胃癌的发生和发展

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安徽医药 2025年第1期29卷 57-62,I0002页

作者：孙颖顾玮王吉郑雄上海交通大学医学院附属瑞金医院卢湾分院消化内科上海200020

目的探讨长链非编码RNA(long non-coding RNA,lncRNA)BBOX1-2通过调控成纤维细胞生长因子受体1(fibroblast growth factor receptor 1,FGFR1)对胃癌的发生发展机制的影响。方法回顾性选取2017年4月至2019年1月于上海交通大学医学院附属... 详细信息

目的探讨长链非编码RNA(long non-coding RNA,lncRNA)BBOX1-2通过调控成纤维细胞生长因子受体1(fibroblast growth factor receptor 1,FGFR1)对胃癌的发生发展机制的影响。方法回顾性选取2017年4月至2019年1月于上海交通大学医学院附属瑞金医院卢湾分院接受胃癌根治术30例病人肿瘤组织及癌旁相应正常组织作为研究对象,采用实时定量PCT(real-time PCR,RT-PCR)检测lncRNA-BBOX1-2和FGFR1表达;si-linc-BBOX1-2转染SGC-7901细胞后,通过蛋白质印迹法/细胞存活率分析(MTT)、细胞迁移和侵袭(Transwell)实验、细胞划痕、平板克隆一系列生物学功能实验,检测肿瘤细胞生物学功能及FGFR1表达的变化。结果胃癌组织中的lncRNA-BBOX1-2(3.68±0.58比1.15±0.11)和FGFR1(4.26±0.71比1.19±0.18)表达显著高于癌旁正常组织(P<0.05);si-linc-BBOX1-2转染SGC-7901细胞后,FGFR1表达下调,细胞活力、迁移、侵袭和生存能力明显下降。结论LincRNA-BBOX1-2可通过调控FGFR1的表达介导胃癌细胞的增殖、凋亡、迁移和侵袭,可能为胃癌的治疗提供了新的靶点和潜在的生物学标志物。

关键词：胃肿瘤长链非编码RNA BBOX1-2 成纤维细胞生长因子受体1 调控增殖凋亡

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Comprehensive Assessment of Urbanization Coordination:A Case Study of Jiangxi Province, China

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Chinese Geographical Science 2019年第3期29卷 488-502页

作者： LI Shu ying Zhixia ZHANG huan GE Gang LIU Qijing Key Laboratory of Poyang Lake Environment and Resource Utilization (Nanchang University) Ministry of Education Department of Environmental Science and Engineering School of Resources Environmental and Chemical Engineering Nanchang University School of Life Sciences Nanchang University College of Forestry Beijing Forestry University

In order to make assessment on urbanization coordination, we developed a comprehensive model by integrating entropy weight method(EWM), coupling degree model(CDM), coupling coordination degree model(CCDM), multi-index grading method(MIGM) and Remote Sensing & Geographic Information System(RS & GIS) technology. Then we applied this integrated model to a case study in Jiangxi Province, China. Our study finds that: 1) EWM, CDM and CCDM can evaluate the temporal dynamic of urbanization. Urbanization process of Jiangxi Province can be divided into three periods, the stable development period(1990–2001), the accelerated development period(2002–2009) and the rapid development period(2010–2015). Coordinated development of urbanization in Jiangxi Province can be divided into two phases, an increasingly coordinated phase(1990–2003) and an increasingly incongruous phase(2003–2015). The state transition was due to low development rate of population urbanization. 2) RS & GIS technology is an effective tool for detecting urban growth. Urban construction land area of Jiangxi Province increased from 615.8 km^2 in 1990 to 2896.8 km^2 in2015, and the per capita urban construction land area(PCUCLA) reached 122.9 m^2, with the maximum value of 343 m^2 in Gongqingcheng City. 3) MIGM and RS & GIS technology can analyze spatial difference of urbanization. There is a significant spatial difference in socioeconomic development at county scale, with the maximum value six times the minimum value for both PCUCLA and per capita GDP in 2015. Population urbanization lag and excessive land use are the main reasons for uncoordinated urbanization. There were 15 counties with a lag in demographic urbanization and 33 counties where PCUCLA exceeded the national standard in 2015, among which 20 exceeded the national standard of PCUCLA by 50%(≥165 m^2). Since there are significant spatio-temporal differences in urbanization, it is necessary to carry out a comprehensive assessment to facilitate differenti

关键词： urban construction land coupling degree model entropy weight method multi-index grading method Remote Sensing & Geographic Information System Technology

Illumination-robust and Anti-blur Feature Descriptors for Image Matching in Abdomen Reconstruction

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International Journal of Automation and computing 2014年第5期11卷 469-479页

作者： huan Liu ying Xiao Wei-Dong Tang Yan-Hui Zhou College of Electronic and Information Engineering Jinggangshan University College of Mechanical and Electronic Engineering Jinggangshan University

This paper puts forward a method for abdomen panorama reconstruction based on a stereo vision system. For the purpose of recovering the abdomen completely and accurately under the condition of actual photographing with illumination variance and blur noise, some innovative combined feature descriptors are presented on the basis of Hu-moment invariants. Furthermore, considering the study on the abdomen surface reconstruction, a circle template which is divided into 6 sectors is designed. It is noted that a descriptor merely using gray intensity is not able to provide sufficient information for feature description. Consequently, the sector entropy which denotes the structure characteristics is drawn into the feature descriptor. By means of the combined effect of the gray intensity and the sector entropy, the similarity measurement is conducted for the final abdomen reconstruction. The experimental results reveal that the proposed method can acquire a high precision of abdomen reconstruction similar to the 3D scanner. This stereo vision system has wide practicability in the field of clothing.

关键词： Stereo vision system illumination-robust and anti-blur combined invariant sector entropy circle template feature matching 3D reconstruction